The description's just an extension of the name, same as for characters. Like, "my network of spies and agents, operating throughout the city-state" is name+description, just like "Tajie, the woman hidden among the horsemen."

Effect is for what the character does and what the particular strength does. Follow the "say what's obvious, plus a detail" rule. "They act for me and report to me. They don't know one another, only me," for my network of agents. For a more magical particular strength, you might write, oh, "I cite occult mantras and twist my hands into difficult poses, and the subtle energies of the world respond to me, enacting of themselves motion, fire and light."